This question demonstrates what can happen if you use rounded numerical results too soon. Always keep enough digits in intermediate calculations to arrive at a final answer with sufficient precision. Consider the following problem. Suppose you want to buy 100 pens. You can buy 100 pens at a 10% discount at one store where the price is $1.99 per pen. And you can also buy 100 pens at a 15% discount at another store where the price is $2.13 per pen. A) What is price per pen at the first store? B) What is the price per pen at the second store?
C) What is the total price difference for 100 pens?

On the way home from visiting his family, vincent’s plane cruised at an altitude of 3.2 × 10^4 feet. he had heard that a man named felix baumgartner skydived from an altitude of 1.28 × 10^5 feet. vincent wants to know how much higher felix went on his skydiving trip. question 1 you have already seen how adding numbers works in either scientific notation or standard notation. but can you subtract numbers in scientific notation and get the same results as subtracting in standard notation? to find out, first solve vincent’s problem in standard notation. part a write the cruising altitude of vincent’s plane in standard notation.